<style>
form{
    border:1px solid #666666;
    border-radius:10px;
    -moz-border-radius:10px;
    height:150px;
    margin:0 auto;
    padding:10px;
    width:200px;
}
.button{
    float:right !important;
}
</style>
<% form_tag :action => "login", :id => @usuario do %>
    <p>
        Email<br />
        <%= text_field_tag "email" %>
    </p>
    <p>
        Senha<br />
        <%= password_field_tag "senha" %>
    </p>
    <p>
        <%= submit_tag "Login", :class => "button" %>
    </p>
<% end %>
